A new study suggests that being exposed to high temperatures during pregnancy can change important nutrients in the body and raise the risk of having a baby early. A premature birth is when a baby is born before 37 weeks.
Researchers already knew that warmer weather is linked to more early births. This new study, published in Science Advances, looks more closely at how heat can affect a pregnant woman’s body.
Heat May Disrupt Important Nutrients in the Blood
Scientists at Emory University studied blood samples from 215 pregnant women in Atlanta, USA. They compared the blood results to the highest temperatures the women experienced during pregnancy.
They found that higher temperatures changed the levels of several important natural substances in the blood, such as:
- Methionine – an essential amino acid from food
- Proline – important for tissue repair
- Citrulline – a compound produced in the body
- Pipecolate – linked to how the body handles stress
These substances help the body use energy and handle physical stress. If their levels change, the risk of problems like preterm birth may go up.
Why Do These Changes Matter?
Lead researcher Donghai Liang said the team used advanced technology to study “molecular fingerprints” in the blood. They found that high heat changed the same molecules that are linked to premature births.
This suggests that heat exposure and premature birth may be connected through the same biological pathways.
How Heat May Affect Pregnancy
Previous research has shown that high temperatures can:
- Increase oxidative stress
- Affect heart function
- Cause inflammation
This study is the first to find specific molecules that are linked to both heat exposure and preterm birth.
For example:
- Each 1°C increase in maximum temperature early in pregnancy was associated with higher methionine levels.
- Heat exposure later in pregnancy was associated with lower levels of citrulline, proline, and pipecolate.
What This Could Mean for Pregnant Women
The researchers believe that their findings could help in the future by:
- Identifying early signs of stress in pregnancy
- Developing tests to check if a pregnancy is at higher risk
- Helping doctors create better prevention strategies
The data came from the “Atlanta African American Maternal-Child Cohort,” which began in 2014.
A Step Toward Better Protection
More research is still needed, but this study shows that climate and rising temperatures can affect the health of pregnant women. Learning about these early changes in the body may help protect future pregnancies and lower the risk of premature births.
